Oxidized sulfur derivatives of diaminophosphinyl compounds as urease inhibitors and urease inhibited urea based fertilizer compositions

ABSTRACT

The invention relates to novel urease inhibited fertilizer compositions containing urea and a urease inhibiting amount of one or more diaminophosphinyl compounds having oxidized sulfur functions, and methods and composition for inhibiting the activity of urease through use of such compounds.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to urease inhibited urea based fertilizercompositions. More particularly, this invention relates to ureaseinhibited urea based fertilizer compositions which contain certaindiaminophosphinyl compounds containing oxidized sulfur functions, as theurease inhibitors, and to methods and compositions for inhibiting theaction of soil urease through use of such compounds.

2. The Prior Art

It is well known in the art to use urea and urea compositions infertilizers, for application to the soil. The effective life of suchfertilizers, however, is of short duration wherever microbiologicalactivity exists in the soil to which the fertilizer is applied. This isdue to the fact that urea is hydrolyzed rapidly, and nitrogen is lost inthe form of ammonia, when urea is placed under or on the surface of soilwhich contains urease. Urease, a crystallizable enzyme occurring innumerous bacteria and fungi, as for example Micrococcus urease,catalyzes the conversion of urea into ammonia and carbon dioxide. Thereactions are as follows: ##STR1##

A portion of the ammonia thus formed is held by absorbing constituentsof the soil and is available to plants as nutrient. However, a largeamount of the ammonia may be lost to the air. A further problemresulting from the action of urease is the accumulation of ammonium inthe soil which can damage germinating seedlings and young plants.

One approach to the reduction of problems resulting from the activity ofsoil urease toward soid applied urea is to find compounds that inhibiturease activity when applied to soils in conjunction with fertilizerurea. This approach has received considerable attention, and severalclasses of compounds have been used as urease inhibitors.

For example, certain prior art describes various phosphoro compoundswhich are useful as urease inhibitors. Illustrative of such prior artare East German Pat. Nos. 142,714; 212,026; 122,177; 122,621 and130,936, and Great Britain Pat. No. 1,494,774 which describe variousphosphorodiamidate compounds as urease inhibitors. Also exemplary ofsuch prior art is U.S. Pat. No. 4,242,325 which describes a method ofcontrolling the enzymatic decomposition of urea to ammonia and carbonicacid due to the action of urease which comprises exposing the enzyme tocertain phosphoric triamide compounds. U.S. Pat. No. 4,182,881describesthe use of certain N-[diaminophosphinyl]arylcarboxyamide compounds asinhibitors of the enzyme urease in the urinary tract. U.S. Pat. No.4,225,526 describes the use of8-[(4-aminophenyl)sulfonyl]amino-2-naphthalenyl phosphorodiamidatecompounds as inhibitors of the enzyme urease, and U.S. Pat. No.4,222,948 describes the use of ([(4-aminophenyl)sulfonyl]amino)phenylphosphorodiamidates as inhibitors of the enzyme urease. Nakanishi, M,and Oe, T, Japan Pat. No. 7379; Chem. Asbtr. 1967, 67, 81947X describescertain diaminophosphinyl compounds containing oxidized sulfur functionsand discloses that such compounds are useful in treating diabetesmellitus.

SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a uniquefertilizer composition comprising urea or one or more compounds whichare capable of forming urea in situ when subjected to the use conditionsof the composition, and a "urease inhibiting effective amount" of one ormore compounds of the formula: ##STR2## wherein: X is oxygen or sulfur;

R₁ is ##STR3## wherein: R₁ ' is amino or substituted or unsubstitutedalkyl, aryl wherein permissible substituents are selected from the groupconsisting of one or more alkyl, aryl, halogen, trihalomethyl, nitro,cyano, alkanoyl, alkylcarboxylate, arylcarboxylate, alkoxy, hydroxy,alkylmercapto, arylmercapto, mercapto, amino, alkylamino, dialkylamino,arylamino, diarylamino, diaminophosphinyl, N-diaminophosphinyl,O-diaminophosphinyl, S-diaminophosphinyl, carbamoyl andcarbamoyldiaminophosphinyl groups;

R₂ is hydrogen, or substituted or unsubstituted alkyl or aryl whereinpermissible substituents are as in R₁ ' above; and

R₃, R₄, R₅ and R₆ are the same or different and are hydrogen or alkylhaving from about 1 to about 4 carbon atoms.

Hereinafter, the aforementioned compounds are referred to as "oxidizeddiaminophosphinyl sulfur derivatives".

Another aspect of this invention relates to a method of enhancing theyield of plants which comprises applying the composition of thisinvention to a plant growth medium within reach of the plant's rootsystem, (hereinafter referred to as "root zone"). The term "plant growthmedium" as herein employed refers to various natural and artificialmedium which support plant growth, including soil, potting mixtures oforganic and inorganic matter, and artificial medium such as polyurethanefoams.

Yet another aspect of this invention relates to a composition comprisinga "urease inhibiting effective amount" of one or more oxidizeddiaminophosphinyl sulfur derivatives, which composition is useful forcarrying out the aformentioned method. As used herein "urease inhibitingeffective amount" is an amount of one or more of the said oxidizeddiaminophosphinyl sulfur derivatives compounds which when admixed withurea (or one or more urea precursor compounds capable of forming urea insitu under the use conditions of the composition); or when applied to asitus, as for example a plant growth medium, is capable of inhibitingthe catalytic activity of urease that may be in or at the medium orother situs to any extent.

It has been discovered by applying a urease inhibiting effective amountof one or more of the oxidized diaminophosphinyl sulfur derivatives to aplant growth medium or other situs the urease catalyzed hydrolysis ofurea which may be present at the situs to ammonia is suppressed, therebypreventing the rapid loss of urea from the situs or medium. Furthermore,by proper distribution and/or application of the one or more oxidizeddiaminophosphinyl sulfur derivatives; this action of inhibiting theurease catalyzed hydrolysis of urea to ammonia is effective over aprolonged period of time.

DETAILED DESCRIPTION OF THE INVENTION

The application and/or distribution of a urease inhibiting effectiveamount of one or more of the above-identified oxidized diaminophosphinylsulfur derivatives to a situs, such as a plant growth medium, orinclusion thereof in a composition and application and/or distributionof the composition to a situs is essential for the practice of thisinvention. While, the oxidized diaminophosphinyl sulfur derivatives canbe used to inhibit the urease catalyzed hydrolysis of urea at any situs,they are especially useful for such inhibition in an agriculturalcontext by application to a plant growth medium. In these preferredembodiments, usually, an acceptable level of urease inhibition can beachieved if at least about 0.01 parts by weight of said one or moreoxidized diaminophosphinyl sulfur derivatives per one million parts byweight of soil or other plant growth medium. Hereinafter theabbreviation "p.p.m." is used to refer to parts by weight of one or moreoxidized diaminophosphinyl sulfur derivatives per one million parts byweight of plant growth medium. In the preferred embodiments of thisinvention, the amount of said one or more oxidized diaminophosphinylsulfur derivatives distributed in the said medium is from about 0.01p.p.m. to about 5,000 p.p.m., and in the particularly preferredembodiments of the invention is from about 0.2 p.p.m. to about 1,000p.p.m. Amongst these particularly preferred embodiments of theinvention, most preferred are those embodiments of the invention inwhich the amount of said one or more oxidized diaminophosphinyl sulfurderivatives distributed in said medium is from about 1 p.p.m. to about500 p.p.m.

Within the aforementioned limitations, the preferred amounts of the oneor more oxidized diaminophosphinyl sulfur derivatives impregnated ordistributed in the plant growth medium are dependent upon the particularsituation. Thus, in determining the amount to be employed, considerationis made not only of the treatment need, i.e., soil pH, temperature, soiltype, and the like, but also of the mode of application to the plantgrowth medium. When the one or more oxidized diaminophosphinyl sulfurderivatives are to be applied in a broadcast application, the amount inp.p.m. may frequently be less than in row or band application where, fora substantial depth and width within the vicinity of application, therecan be a very high concentration of the one or more such compounds. Whenapplication is made near the root zone of growing plants, or whenapplication is made immediately prior to seeding or transplanting, theamounts supplied are frequently at a lower rate than when application ismade at the end of the growing season to prepare the plant growth mediumfor the following season. By dispersing very large dosages in the plantgrowth medium, a prolonged inhibition of urease activity can be obtainedover a period of many months. The concentration of the one or moreoxidized diaminophosphinyl sulfur derivatives is eventually reduced to aminimum by decomposition in the plant growth medium.

In one method for carrying out the present invention, one or moreoxidized diaminophosphinyl sulfur derivatives are distributed throughoutthe plant growth medium in a broadcast application, such as by spraying,dusting, distributing in irrigation water and the like. In suchapplication, the one or more oxidized diaminophosphinyl sulfurderivatives are supplied in amounts sufficient to permeate the growingarea of the medium with a urease inhibiting effective amount of suchoxidized diaminophosphinyl sulfur derivatives. In field administration,the one or more "oxidized sulfur diaminophosphinyl derivative" compoundscan be distributed in the plant growth medium in an amount and throughsuch cross-section of the medium as to provide for the presence thereinof a urease inhibiting effective amount of the one or more oxidizeddiaminophosphinyl sulfur derivatives. It is usually preferred that theone or more oxidized diaminophosphinyl sulfur derivatives be distributedin the plant growth medium to a depth of at least two inches below thesurface of the plant growth medium.

In another method for carrying out the present invention, one or moreoxidized diaminophosphinyl sulfur derivatives are administered to theplant growth medium in a band or row application. In such application,administration is made with or without carrier in amounts sufficient tosupply to the soil or other plant growth medium a urease inhibitingeffective amount of the one or more oxidized diaminophosphinyl sulfurderivatives. After administration with or without discing or dragging,subsequent irrigation or rainfall distributes the one or more oxidizeddiaminophosphinyl sulfur derivatives throughout the plant growth medium.

In one embodiment of the present invention, the one or more oxidizeddiaminophosphinyl sulfur derivatives are distributed throughout thegrowth medium prior to seeding or transplanting the desired crop plant.

In another embodiment, the soil or plant growth medium within the rootzone of growing plants is treated with the one or more oxidizeddiaminophosphinyl sulfur derivatives in an amount effective to inhibitthe action of urease, but sublethal to plant growth. By following suchpractice, no adverse effect is exerted by the one or more oxidizeddiaminophosphinyl sulfur derivatives upon growth of seeds or plants.Oftentimes, it is desirable to treat the soil adjacent to plants, andthis procedure may be carried out conveniently in side-dressingoperations.

In a further embodiment of the invention, soil or other plant growthmedium is treated with one or more oxidized diaminophosphinyl sulfurderivatives following harvest to prevent rapid loss of urea, and toprevent build-up of soil urease. Such practice conserves the soilnitrogen for the following growing season. In such application, theupper limit is primarily an economic consideration.

In an additional embodiment, the soil or plant growth medium can beimpregnated with the one or more oxidized diaminophosphinyl sulfurderivatives in conjunction with the application of urea or one or moreurea precursor compounds capable of forming urea in situ on applicationto the plant growth medium. Urea is a well known, commercially availablecompound and will not be discussed herein in detail. Illustrative ofcompounds which are believed to form urea on addition to the soil andare water soluble and formaldehyde condensation products, as for examplemethylolureas, methyleneureas and mixtures thereof. These products and amethod for their preparation is described in detail in Justice U.S. Pat.No. 3,462,256. Still other useful sources of urea are water-insolubleurea formaldehyde condensation products such as ureaform. Illustrativeof useful water-insoluble urea and formaldehyde condensation productsare those whose preparation and use are described in detail in U.S. Pat.Nos. 3,677,736 and 4,033,745.

The present invention can be carried out by distributing one or moreoxidized diaminophosphinyl sulfur derivatives in an unmodified formthrough a plant growth medium. The present method also embracesdistributing one or more such compounds as a constituent in liquid orfinely divided solid compositions.

The concentration of the one or more oxidized diaminophosphinyl sulfurderivatives in compositions to be employed for the treatment of a plantgrowth medium is not critical and can vary considerably provided therequired dosage of the effective agents is supplied to the growthmedium. In general, good results are obtained with liquid and/or solidcompositions containing at least about 0.00001 percent by weight of theone or more oxidized diaminophosphinyl sulfur derivatives. Usually,however, the weight percent of the one or more oxidizeddiaminophosphinyl sulfur derivatives is from about 0.0001 percent toabout 98 percent by weight on the same basis. In the preferredembodiments of the invention, the amount of the one or more oxidizeddiaminophosphinyl sulfur derivatives in the composition is from about0.002 to about 50 weight percent, and in the particularly preferredembodiments is from about 0.01 to about 20 weight percent on theaforementioned basis. Liquid or dust compositions in which the one ormore oxidized diaminophosphinyl sulfur derivatives is present in higherconcentration can be utilized as such or can be employed as concentratecompositions to be diluted to prepare actual treating compositions.

In such practice, the one or more oxidized diaminophosphinyl sulfurderivatives can be modified with one or more additiments or soiltreating adjuvants including water, petroleum distillates or otherliquid carriers, surface-active dispersing agents, inert finely dividedsolids, and fertilizers, as for example urea, the afore-mentioned ureaprecursor compounds, and reduced nitrogen fertilizers such as ammoniumnitrate and ammonia. These adjuvants cooperate with the one or moreoxidized diaminophosphinyl sulfur derivatives so as to facilitate thepractice of the present invention and to obtain an improved result.Preferred adjuvants are surface-active dispersing agents, inert finelydivided solids and urea and/or urea precursor compounds. The amount ofurea or urea precursor compound which may be included in the compositionof this invention is not critical to the unique advantages thereof, andany amount known to those of skill in the art for use in fertilizers canbe used. Normally, the amount employed will vary widely depending on anumber of factors, including the times and frequency of application. Inthe preferred embodiments of the invention, the quantity of urea or ureaprecursor compound may vary from about 0.5 to about 95 weight percentbased on the total weight of the composition and in the particularlypreferred embodiments may vary from about 1 to about 50 weight percenton the same basis. In the most preferred embodiments of this invention,the quantity of urea or urea precursor compound will vary from about 3to about 40 weight percent on the aforementioned basis.

The composition of this invention may include other optional ingredientsknown to those of skill in the art for inclusion in fertilizercompositions. For example, the composition may include sources ofpotassium, sulfur, phosphorus, boron, zinc, iron, manganese, copper,molybdenum, cobalt and like micronutrient and macronutrients which maybe deficient in the soil. The composition may also include plant growthregulators, as for example auxins, cytokinins and the like, as well aspesticides, such as insecticides, miticides, herbicides, nemitocides andthe like. Moreover, the fertilizer composition can include sources ofnitrogen other than urea, as for example ammonium nitrate and the like,and other materials which increase nitrogen efficiency, as for example,other urease inhibitors and nitrification inhibitors. Depending upon theconcentration of the one or more oxidized diaminophosphinyl sulfurderivatives, augmented compositions can be distributed in the plantgrowth medium without further modification or can be considered asconcentrates and subsequently diluted with additional inert carriers toproduce the ultimate treating composition.

Liquid compositions containing the desired amount of the one or moreoxidized diaminophosphinyl sulfur derivatives can be prepared bydispersing the latter in one or more liquid carriers such as water or anorganic solvent with or without the aid of a suitable surface activedispersing agent or emulsifying agent. Suitable organic solvents includeacetone, diisobutylketone, methanol, ethanol, isopropyl alcohol, diethylether, toluene, methylene chloride, chlorobenzene and petroleumdistillates. The preferred organic solvents are those which are of suchvolatility that they leave little permanent residue in the growthmedium. Dispersing and emulsifying agents which can be employed inliquid compositions include condensation products of alkylene oxideswith phenols and organic acids, alkyl aryl sulfonates, polyoxyalkylenederivatives or sorbitol esters, sugar esters, complex ether alcohols,mahogany soaps and the like. The surface active agents are generallyemployed in the amount of from about 1 to about 20 percent by weight ofthe oxidized diaminophosphinyl sulfur derivatives and preferably in anamount of from about 1 to about 10 weight percent on the same basis.

Solid compositions containing the active one or more oxidizeddiaminophosphinyl sulfur derivatives can be prepared by dispersing thelatter in finely divided inert solid carriers such as talc, chalk,gypsum, vermiculite, bentonite and the like, fuller's earth, attapulgiteand other clays, various solid detergent dispersing agents and solidfertilizer compositions. In preparing such compositions, the carrier ismechanically ground with a solid one or more oxidized diaminophosphinylsulfur derivatives; or wet with a liquid one or more oxidizeddiaminophosphinyl sulfur derivatives; or wet with a solution ordispersion of a solid or liquid one or more oxidized diaminophosphinylsulfur derivatives in a volatile organic solvent. Depending upon theproportions of ingredients, these compositions can be employed withoutfurther modification or be considered concentrates and subsequentlyfurther diluted with solid surface active dispersing agents, talc,chalk, gypsum, bentonite, diatomaceous earth, fullers earth, or the liketo obtain the desired treating composition. Furthermore, suchconcentrate compositions can be dispersed in water with or without addeddispersing agent or agents to prepare aqueous soil treatingcompositions.

The required amount of the one or more oxidized diaminophosphinyl sulfurderivatives contemplated herein may be applied per acre treated in fromabout 1 to about 200 gallons or more of liquid carrier and/or diluent orin from about 5 to about 500 pounds of inert solid carrier and/ordiluent. The concentration in the liquid concentrate will usually varyfrom about 10 to about 95 percent by weight and in the solidformulations from about 0.5 to about 90 percent by weight. Satisfactorysprays, dusts, or granules for general use contain from about 1/4 toabout 15 pounds of active one or more oxidized diaminophosphinyl sulfurderivatives per acre.

The compounds contemplated herein prevent or retard the urease catalyzedhydrolysis of urea, and they have relatively high residual activity.With respect to plants they have a high margin of safety in that whenused in sufficient amount to inhibit the activity of urease, they do notburn or injure the plant, and they resist weathering which includeswash-off caused by rain, decomposition by ultraviolet light, oxidation,or hydrolysis in the presence of moisture or, at least suchdecomposition, oxidation, and hydrolysis as would materially decreasethe desirable urease inhibiting characteristic of the compounds orimpart undesirable characteristics, for instance, phytotoxicity, to thecompounds. The compounds are so chemically inert that they arecompatible with substantially any other constituents of the sprayschedule, and they may be used in the soil, upon the seeds, or the rootsof plants without injuring either the seeds or roots of plants.

While the composition and method of this invention are particularlysuited for agricultural applications for prevention or inhibition ofurease catalyzed hydrolysis of urea, they can also be used in otherapplications where inhibition of the activity of urease is desired. Forexample, such other applications include use in animal litters, as feedadditives, pharmaceutical applications, diaper treatment, ureaseinhibition in mammalian urinary tracts, and the like. It should be notedthat while all of the above-identified compounds exhibit ureaseinhibiting activity, the particular active compound employed in oneapplication may not necessarily be useful in another application. Thus,in the selection of a particular active compound for use in anapplication, such factors are toxicity of the compound, the environmentin which the compound will be used, level of urease inhibition desiredand the like must be considered in selecting a particular compound foruse.

Diaminophosphinyl compounds which are useful as urease inhibitors in thecomposition of this invention are those of the formula: ##STR4##wherein: X is oxygen or sulfur;

R₁ is ##STR5## wherein R₁ ' is amino or substituted or unsubstitutedalkyl, aryl wherein permissible substituents are selected from the groupconsisting of one or more alkyl, aryl, halogen, trihalomethyl, nitro,cyano, alkanoyl, alkylcarboxylate, arylcarboxylate, alkoxy, hydroxy,alkylmercapto, arylmercapto, mercapto, amino, alkylamino, dialkylamino,arylamino, diarylamino, diaminophosphinyl, N-diaminophosphinyl,O-diaminophosphinyl, S-diaminophosphinyl, carbamoyl andcarbamoyldiaminophosphinyl groups;

R₂ is hydrogen, or substituted or unsubstituted alkyl or aryl wherepermissible substituents are as in R₁ above; and

R₃, R₄, R₅ and R₆ are the same or different and are hydrogen or alkylhaving from about 1 to about 4 carbon atoms.

Examples of R₁ ' include methyl, ethyl, isopropyl, tert-butyl, n-octyl,cyclohexyl, trichloromethyl, trifluoromethyl, 2-chloroethyl, phenyl,p-tolyl, 4-nitrophenyl, 3-chlorophenyl, 2-nitrophenyl,N,N-diphenylamino, 4-morpholine, pentamethyleneamino,N,N-dicyclohexylamino, N-diaminophosphinyl,4-[O-(diaminophosphinyl)phenyl], 4-[N-(diaminophosphinyl)phenyl],3-cyanophenyl, and the like.

Examples of R₂ include hydrogen, methyl, ethyl, phenyl, 2-chloroethyl,4-nitrophenyl, 3-methyoxyphenyl, 2-methylmercaptoethyl, and the like.

Examples of R₃, R₄, R₅, and R₆ include hydrogen, methyl, ethyl,n-propyl, isopropyl, and tert-butyl.

Specific examples of other such compounds which would be expected to begood urease inhibitors include:

N-(Diaminophosphinyl)-4-methoxybenzenesulfonamide

N-(Diaminophosphinyl)-4-nitrobenzenesulfonamide

N-(Diaminophosphinyl)-3-chlorobenzenesulfonamide

N-(Diaminophosphinyl)methylsulfonamide

N-(Diaminophosphinyl)ethylsulfonamide

N-(Diaminophosphinyl)trichloromethylsulfonamide

N-(Diaminophosphinyl)trifluoromethylsulfonamide

N-(Diaminophosphinyl)sulfamide

N-(Diaminophosphinyl)-N'-methylsulfamide

N-(Diaminophosphinyl)-N',N'-diethylsulfamide

N-(Diaminophosphinyl)-N'-ethylsulfamide

N-(Diaminophosphinyl)-N',N'-dimethylsulfamide

N-(Diaminophosphinyl)-N',N'-dipropylsulfamide

N-(Diaminophosphinyl)-4-morpholinesulfamide

N-(Diaminophosphinyl)-N',N'-pentamethylenesulfamide

N-(Diaminophosphinyl)-N'-cyclohexylsulfamide

N-(Diaminophosphinyl)-N'-phenylsulfamide

N-(Diaminophosphinyl)-N',N'-diphenylsulfamide

N-(Diaminophosphinyl)-N'-methylbenzenesulfonamide

N-(N'-Methyldiaminophosphinyl)benzenesulfonamide

N-(N',N"-Diethyldiaminophosphinyl)-4-toluenesulfonamide

N-(N',N"-Dimethyldiaminophosphinyl)benzenesulfonamidebis-N-(Diaminophosphinyl)sulfamide

N-(Diaminothiophosphinyl)benzenesulfonamide

N-(Diaminothiophosphinyl)-p-toluenesulfonamide

N-(Diaminothiophosphinyl)-N',N'-diethylsulfamide

N-(Diaminothiophosphinyl)-N'-butylsulfamide

N-(Diaminothiophosphinyl)-N'-methylbenzenesulfonamide

N-(N'-Methyldiaminothiophosphinyl)-N-methylbenzenesulfonamide

N-(Diaminothiophosphinyl)trichloromethylsulfonamide

N-(Diaminothiophosphinyl)trifluoromethylsulfonamide

N-(Diaminothiophosphinyl)methylsulfonamide

N-(Diaminothiophosphinyl)-N-tert-butylpropylsulfonamide

N-(N'-Methyldiaminothiophosphinyl)ethylsulfonamidebis-N-(Diaminothiophosphinyl)sulfamide

N-(Diaminophosphinyl)-N'-(2-chloroethyl)sulfamide

N-(Diaminophosphinyl)-N-(2'-methylmercaptoethyl)benzenesulfonamide

N-(Diaminophosphinyl)-N-(3'-methoxyphenyl)-4-toluenesulfonamide

N-(Diaminophosphinyl)benzenesulfinamide

N-(Diaminophosphinyl)-4-toluenesulfinamide

N-(Diaminophosphinyl)-3-methoxybenzenesulfinamide

N-(Diaminophosphinyl)-2-nitrobenzenesulfinamide

N-(Diaminophosphinyl)-4-chlorobenzenesulfinamide

N-(Diaminophosphinyl)-N-methyl-4-cyanobenzenesulfinamide

N-(Diaminophosphinyl)-N-ethyl-3-trichloromethylbenzenesulfanomide

N-(Diaminophosphinyl)-4-trifluoromethylbenzenesulfonamide

N-(Diaminophosphinyl)-N-phenylbenzenesulfinamide

N-(Diaminophosphinyl)-N'-methyl-4-methylmercaptobenzesulfanimide

N-(Diaminophosphinyl)-4-(N',N'-dimethylaminobenzenesulfinamide

N,4-bis-Diaminophosphinyl)sulfanilamide

N,O-bis-(Diaminophosphinyl)-4-hydroxybenzenesulfonamide

N,S-bis-(Diaminophosphinyl)-3-mercaptobenzenesulfonamide

N-(Diaminophosphinyl)-2-bromobenzenesulfonamide

N-(Diaminophosphinyl)-4-iodobenzenesulfonamide

N-(Diaminophosphinyl)-N-isopropyl-4-cyanobenzenesulfonamide

N-(Diaminophosphinyl)-4-acetylbenzenesulfonamide

N-(Diaminophosphinyl)-4-tert-butylbenzenesulfonamide

N-(Diaminophosphinyl)-3-(N',N'-dimethylamino)benzenesulfonamide

N-(Diaminophosphinyl)-6-methoxycarbonyl-n-hexylsulfamide

N,N-bis-(Diaminophosphinyl)-4-carbamoylbenzenesulfonamide

N-(Diaminophosphinyl)-tert-butylsulfinamide

N-(Diaminophosphinyl)trichloromethylsulfinamide

N-(Diaminothiophosphinyl) benzenesulfinamide

N-(Diaminothiophosphinyl)-4-toluenesulfinamide

N-(Diaminothiophosphinyl)-3-nitrobenzenesulfinamide

N-(Diaminothiophosphinyl)-2-ethoxybenzenesulfinamide

N-(Diaminothiophosphinyl)-N-methyl-4-chlorobenzenesulfinamide

N-(Diaminothiophosphinyl)-N-ethyl-3-toluenesulfinamide

N-(Diaminothiophosphinyl)-4-trichloromethylbenzenesulfinamide

N-(N"-Methyldiaminothiophosphinyl)-N'-methylbenzenesulfinamide

N-(N'-Methyldiaminothiophosphinyl)-N-propylbenzenesulfinamide

N-(Diaminothiophosphinyl)-N,N',N'-trimethylsulfamide

N-(Diaminothiophosphinyl)-N'-benzyl-N'-methylsulfamide

N-(Diaminothiophosphinyl)-N'-ethyl-N-methylsulfamide

N-(Diaminothiophosphinyl)-N'-phenyl-N-isopropylsulfamide

N-(Diaminothiophosphinyl)-N'-tert-butyl-N-ethylsulfamide

N-(Diaminothiophosphinyl)-N',N'-dibutyl-N-ethylsulfamide

N-(Diaminothiophosphinyl)-N'-phenyl-N-propylsulfamide

N-(Diaminothiophosphinyl)-N-butyl-N',N'-dimethylsulfamide

N-(Diaminothiophosphinyl)-tert-butylsulfinamide

N-(Diaminothiophosphinyl)trifluoromethylsulfinamide

N-(Diaminothiophosphinyl)-N'-methyl-N'-octylsulfamide

N-(N"-Methyldiaminothiophosphinyl)-N',N'-diisopropylsulfamide

Preferred for use in the practice of this invention are compounds of theaforementioned generic formula in which X is oxygen.

Particularly preferred for use in the practice of this invention arecompounds of the aforementioned generic formula in which:

X is oxygen;

R₁ is ##STR6## wherein: R₁ ' is alkyl, cycloalkyl, phenyl, alkylphenyl,or phenylalkyl;

R₂ is hydrogen, or R₁ '; and

R₃, R₄, R₅ and R₆ are hydrogen.

Amongst these particularly preferred compounds most preferred are thosecompounds is which:

X is oxygen;

R₁ is ##STR7## wherein R₁ ' is alkyl having from about 1 to 7 carbonatoms, phenyl, or phenylalkyl or alkylphenyl having from about 7 toabout 12 carbon atoms;

R₂ is hydrogen or R₁ ; and

R₃, R₄, R₅ and R₆ are hydrogen.

Especially effacious compounds for use in practice of this invention areN-(diaminophosphinyl)-p-toluenesulfonamide andN-(diaminophosphinyl)benzenesulfonamide.

Compounds for use in the practice of this invention in which X is oxygencan be conveniently prepared in accordance with the following ReactionScheme A: ##STR8## wherein R₁, R₃, R₄, R₅ and R₆ are as identifiedhereinabove.

Alternatively, compounds for use in the practice of this invention canbe prepared according to the following Reaction Scheme B: ##STR9##wherein R₁, R₂, R₃, R₄, R₅ and R₆ are as described above, and Y is aleaving group, such as flouride, chloride, bromide, iodide, alkylester,or the like.

Examples of compounds prepared by Reaction Scheme A are given inNakanishi, M.; Oe, Ti; Japan Pat. No. 7379 (1967); Chem. Abstr. 1967,67, 81947X. Examples of the preparation of sulfonylphosphoramidicdichlorides, sulfamoylphosphoramidic dichlorides andsulfonylbis(phosphoramidic trichlorides) are summarized by Nielsen, M.L. in "Developments in Inorganic Nitrogen Chemistry", Cobern, C. B.,ed., Elsevier Publishing Co., New York, 1966, Ch V, pp 394, 436-37, and448-49. The preparation of N,N-dialkylsulfamides is disclosed by Vandi,A. and Moeller, T. in "Inorganic Synthesis," Holtzshaw, H. F., Jr., ed.,McGraw-Hill Book Co., New York, 1966. Vol VIII, pp 111-116, andreferences cited therein. The preparation of dialkylamides of(trichlorophosphoranylidene)sulfamic acids is described by Vandi, A. andMoeller, T., ibid., pp 116-119, and cited references therein. Thepreparation of bis(trichorophosphoranylidene)sulfamide is described byVandi, A. and Moeller, T., ibid., pp 119-121, and references citedtherein.

Briefly stated, in each step of the above reaction schemes,substantially equal molar amounts or excesses of the reactants arecontacted neat or in an inert solvent. Useful inert reaction solventsinclude ethyl ether, carbon tetrachloride, methylene chloride, glyme,benzene, dioxane, toluene, xylene, tetrahydrofuran, methyl sulfoxide,dimethylformamide and the like.

In those reaction steps in which hydrogen chloride is produced an acidacceptor can be used.

The hydrogen chloride acid acceptor employed is a basic material whichcan be either an inorganic or organic base. Suitable inorganic basesinclude alkali metal carbonates such as sodium carbonate, potassiumcarbonate and the like. Organic bases which are useful and preferred foruse in this invention are tertiary amines, as for example pyridine,lutidine, 1,4-diazabicyclo[2.2.2]octane, isoquinoline, quinoline,N-methylpiperidine, trimethylamine, triethylamine, and the like.

Reaction temperatures and pressures are not critical. The reaction canbe conveniently carried out at a temperature of from about -80° C. toabout 200° C., but is preferably carried out at a temperature of fromabout -30° C. to about 150° C. The reaction can be carried out atatmospheric, sub-atmospheric or super-atmospheric pressure. Forconvenience, however, the reaction is carried out at atmospheric orautogeneous pressure.

The order in which the reactants are reacted indicated in the reactionscheme is for illustrative purposes only, and the order of the reactionsis not critical. The exact proportions of the reactants are notcritical, some of the desired product can be obtained when the reactantsare employed in any proportions.

Reaction times are not critical and can be varied widely depending onsuch factors as the reaction temperature, reactivity of the reactants,and the like. The reaction mixture is usually held within the desiredreaction temperature range for a period of time, conveniently from about30 minutes to about 72 hours before cooling. Good yields are obtainedwith reaction times of from 1 to about 8 hours.

After the reactions have gone substantially to completion, the productcan be separated by such conventional procedures as evaporation, andpurified by conventional procedures such as distillation and extraction.The product separated as described above can be employed in the controlof urease in the soil or in other applications in accordance with thisinvention or may be further purified by conventional procedures such asextraction and distillation.

The following specific examples are presented to more particularlyillustrate the invention.

EXAMPLE I Preparation of N-(Diaminophosphinyl)-p-toluene-sulfonamide

A mixture of 51.4 g (0.300 mol) of p-toluenes ulfonamide, 62.5 g (0.300mol) of phosphorus pentachloride, and 500 mL of carbon tetrachloride wasprepared under a nitrogen atmosphere in a dry 1000 mL, round bottomflask fitted with a mechanical stirrer and a condenser attached to asodium hydroxide trap. The stirred mixture was gradually heated to 75°C. During this process hydrogen chloride steadily began to evolve. Themixture was heated for 60 h at 75° C. during which time gas evolutionceased and the solution became homogeneous. Upon cooling, however, thereaction mixture gelled into a slightly pink solid. The flask wasrewarmed to 55° C. to redissolve the solid, the heating bath wasremoved, and 11.8 mL (14.4 g, 0.315 mol) of formic acid was addeddropwise over a 20 min period. Gases were vigorously evolved during thisprocess and the color of the solution became yellow. The solution wasstirred for another 2 h without external heating and then for 1 h at 55°C. The mixture was cooled to ambient temperature causing two layers toform in the flask. Analysis of each layer, however, showed them to besubstantially the desired product, and, upon standing under nitrogen,each layer crystallized into a solid, mp 114°-118° C. and 118°-121° C.(upper and lower layers, respectively). The solids, 64 g from the upperlayer and 28 g from the lower layer, were combined and extracted with1200 mL of hot carbon tetrachloride. The mixture was filtered free from5-10 g of residue, and 46.7 g (54%) pure p-toluenesulfonylphosphoramidicdichloride, mp 115.5°-117.5° C. (lit. mp 115°-118° C.) was obtained byallowing the filtrate to crystallize.

¹ H NMR (CDCl₃): δ 8.82 (S, 1H, NH), 7.83 (d, J=8 Hz, 2H, ArH), 7.28 (d,J=8 Hz, 2H, ArH), and 2.43 ppm (s, 3H, CH₃).

The p-toluenesulfonylphosphoramidic dichloride (46.7 g, 0.162 mol) wasdissolved in 200 mL of ether and added dropwise over a 2 h period to awell stirred solution of 75 mL of ammonia (about 3 mol) in 300 mL ofether at -30° to -35° C. The mixture was stirred for another 1.5 h whileallowing the ammonia to maintain itself at reflux, and then for another30 min under a nitrogen purge to remove excess ammonia. The still coolmixture was filtered, and the resulting white solid was washed well withether. After being dried under nitrogen, 59.4 g (80%) of white solidcomposed of 70% (by weight) ofN-(diaminophosphinyl)-p-toluenesulfonamide and 30% (by weight) ofammonium chloride was obtained. Since the desired product was insolublein chloroform and related solvents, this mixture was used directly inurease inhibition studies.

'H NMR (D₂ O): δ 7.80 (d, J=8 Hz, 2H, ArH), 7.35 (d, J=8 Hz, 2H, ArH),and 2.38 ppm (s, 3H, CH₃).

³¹ P NMR (D₂ O): δ 10.4 ppm.

¹³ C NMR (Proton Decoupled in D₂ O): δ 21.31 (s, 1C, CH₃), 126.41 (s,2C, ArC ortho to SO₂ NH--), 130.22 (s, 2C, ArC meta to SO₂ NH--), 142.29(s, 1C, ArC ipso to SO₂ NH--), and 143.42 ppm (s, 1C, ArC para to SO₂NH--).

Mass Spectrum (70 eV) of sample derivatized with "Methyl-8" reagent(DMF-Dimethylacetal) corresponding to p-CH₃ C₆ H₄ SO₂ NHP(O)[N═CHN(CH₃)₂]₂ : m/e 359 (M⁺), 295 (M⁺ --SO₂), 189, 162, and 135. A peak at m/e 373with a fragment at 309 was also present, and indicated that amethoxylated derivative was also formed.

Infrared (KBr): 3700-2500 (br, s, NH & NH₄ Cl, 1630 (w), 1565 (s), 1400(s), 1210 (s), 1078 (s), 940 (s), 755 (w), 729 (w), 690.(w), 610.(w),510 (m), and 360 cm ⁻¹ (m).

EXAMPLE II Preparation of N-(Diaminophosphinyl)benzenesulfonamide

Into a 65 mL round bottom flask containing a stirrer was suspended 4.80g (50 mmol) of phosphoric triamide in 20 mL of chloroform. To this wasadded 4.04 mL of pyridine (50 mmol). An addition funnel was placed ontop of a condenser which was then attached to the flask. The system waspurged with nitrogen, and 6.38 mL (50 mmol) of benzenesulfonyl chloridein 10 mL of chloroform was placed in the addition funnel. Thebenzenesulfonyl chloride solution was added dropwise over a 15 minperiod to give a somewhat exothermic reaction and a light yellow color.After stirring for 1 h at room temperature, the flask was then heated at55°-60° C. for 60 h. The mixture was then cooled, and the resultingsolids were broken-up, collected by filtration, washed well with 3×50 mLof chloroform, and dried under nitrogen to give 6.38 g (55%) of whiteproduct. The ¹ H NMR in D₂ O showed two aromatic multiplets centered atw 7.87 and 7.68 ppm as well as about 20% pyridine hydrochloride as animpurity.

EXAMPLE III

Efficacy tests were conducted to evaluate the efficacy of certainrepresentative oxidized sulfur derivatives of diaminophosphinylcompounds as urease inhibitors. The inhibition tests were run in NewYork (Cazenovia Silt loam, pH 7.3) and Wisconsin (Plano silt loam pH5.3) soils. Evaluations (run in triplicate) consisted of applying 800micrograms of the test compound in 5 mL of water and 42.8 mg of urea in1 mL of water to 20 g of air-dry soil in a glass bottle. The bottle wascapped with perforated aluminum foil and incubated at 25° C. for threedays prior to extraction with 100 mL of a 2M potassium chloride solutioncontaining 0.5 mg of phenylmercuric acetate. The extracts were thenanalyzed for remaining urea using an autoanalyzer. Percent inhibitionwas calculated as ##EQU1## where A is urea recovered from unincubatedsample (urea added to soil and immediately extracted); B is urearecovered from inhibited sample; and C is urea recovered from thecontrol (uninhibited sample).

The results of these test are set forth in the following Table I.

                  TABLE I                                                         ______________________________________                                                           % Inhibition                                                                  40 Micrograms                                                                 per gram soil                                              Experiment               Cazenovia Wisconsin                                  Number  Compound         pH 7.3    pH 5.3                                     ______________________________________                                        1.      N--(Diaminophosphinyl)-                                                                        86        51                                                 p-toluenesulfonamide                                                  2.      N--(Diaminophosphinyl)-                                                                        91        23                                                 benzenesulfonamide                                                    ______________________________________                                    

What is claimed is:
 1. A urease inhibiting composition comprising acarrier and a urease inhibiting effective amount of one or morecompounds of the formula: ##STR10## wherein: X is oxygen or sulfur;R₁ is##STR11## wherein; R₁ ' is amino or substituted or unsubstituted alkyl,aryl wherein permissible substituents are selected from the groupconsisting of one or more alkyl, aryl, halogen, trihalomethyl, nitro,cyano, alkanoyl, alkylcarboxylate, arylcarboxylate, alkoxy, hydroxy,alkylmercapto, arylmercapto, mercapto, amino, alkylamino, dialkylamino,arylamino, diarylamino, diaminophosphinyl, N-diaminophosphinyl,O-diaminophosphinyl, S-diaminophosphinyl, carbamoyl andcarbamoyldiaminophosphinyl groups; and R₂ is hydrogen, or substituted orunsubstituted alkyl or aryl wherein permissible substituents areselected from the group consisting of one or more alkyl, aryl, halogen,trihalomethyl, nitro, cyano, alkanoyl, alkylcarboxylate,arylcarboxylate, alkoxy, hydroxy, alkylmercapto, arylmercapto, mercapto,amino, alkylamino, dialkylamino, arylamino, diarylamino,diaminophosphinyl, N-diaminophosphinyl, O-diaminophosphinyl,S-diaminophosphinyl, carbamoyl and carbamoyldiaminophosphinyl groups;and R₃, R₄, R₅ and R₆ are the same or different and are hydrogen oralkyl having from about 1 to about 4 carbon
 2. A composition accordingclaim 1 wherein X is oxygen.
 3. A composition according to claim 1wherein X is sulfur.
 4. A composition according to claim 1 wherein:R₁ is##STR12##
 5. A composition according to claim 4 wherein R₁ ' is alkyl,cycloalkyl, phenyl, phenylalkyl or alkylphenyl.
 6. A compositionaccording to claim 5 wherein R₁ ' is phenyl or alkylphenyl having fromabout 7 to about 12 carbon atoms.
 7. A composition according to claim 6wherein R₁ ' is alkylphenyl.
 8. A composition according to claim 1wherein R₂ is hydrogen or a substituent selected from the groupconsisting of permissible R₁ ' substituents.
 9. A composition accordingto claim 8 wherein R₂ is hydrogen.
 10. A composition according to claim1 wherein R₃, R₄, R₅ and R₆ are hydrogen.
 11. A composition according toclaim 1 wherein said one or more compounds are selected from the groupconsisting of N-(diaminophosphinyl)-p-toluenesulfonamide andN-(diaminophosphinyl)benzenesulfonamide.
 12. A composition according toclaim 1 wherein said urease inhibiting amounts is at least about 0.00001weight percent based on the total weight of the composition.
 13. Acomposition according to claim 12 wherein said amount is from about0.0001 to about 98 weight percent.
 14. A composition according to claim13 wherein said amount is from about 0.002 to about 50 weight percent.15. A composition according to claim 14 wherein said amount is fromabout 0.01 to about 20 weight percent.
 16. An fertilizer compositionwhich comprises a carrier, urea and/or one or more urea precursorcompounds capable of forming urea in situ when subjected to the useconditions of the composition, and a urease inhibiting effective amountof one or more compounds of the formula: ##STR13## wherein: X is oxygenor sulfur;R₁ is ##STR14## wherein R₁ ' is amino or substituted orunsubstituted alkyl or aryl wherein permissible substituents areselected from the group consisting of one or more alkyl, aryl, halogen,trihalomethyl, nitro, cyano, alkanoyl, alkylcarboxylate,arylcarboxylate, alkoxy, hydroxy, alkylmercapto, arylmercapto, mercapto,amino, alkylamino, dialkylamino, arylamino, diarylamino,diaminophosphinyl, N-diaminophosphinyl, O-diaminophosphinyl,S-diaminophosphinyl, carbamoyl and carbamoyldiaminophosphinyl; R₂ ishydrogen, or substituted or unsubstituted alkyl or aryl whereinpermissible substituents are selected from the group consisting of oneor more alkyl, aryl, halogen, trihalomethyl, nitro, cyano, alkanoyl,alkylcarboxylate, arylcarboxylate, alkoxy, hydroxy, alkylmercapto,arylmercapto, mercapto, amino, alkylamino, dialkylamino, arylamino,diarylamino, diaminophosphinyl, N-diaminophosphinyl,O-diaminophosphinyl, S-diaminophosphinyl, carbamoyl andcarbamoyldiaminophosphinyl; above; and R₃, R₄, R₅ and R₆ are the same ordifferent and are hydrogen or alkyl having from about 1 to about 4carbon atoms.
 17. A composition according to claim 16 wherein X isoxygen.
 18. A composition according to claim 16 wherein X is sulfur. 19.A composition according to claim 16 whereinR₁ is ##STR15##
 20. Acomposition according to claim 19 wherein R₁ ' is alkyl, cycloalkyl,phenyl, phenylalkyl or alkylphenyl.
 21. A composition according to claim19 wherein R₁ ' is phenyl or alkylphenyl having from about 7 to about 12carbon atoms.
 22. A composition according to claim 21 wherein R₁ ' isalkylphenyl.
 23. A composition according to claim 16 wherein R₂ ishydrogen or a substituent selected from the group consisting ofpermissible R₁ substituents.
 24. A composition according to claim 23wherein R₂ is hydrogen.
 25. A composition according to claim 16 whereinR₃, R₄, R₅ and R₆ are hydrogen.
 26. A composition according to claim 16wherein said one or more compounds are selected from the groupconsisting of N-(diaminophosphinyl)-p-toluenesulfonamide andN-(diaminophosphinyl)benzenesulfonamide.